Last year Shannon listened to a certain public radio station 10 hours

Question

Last year Shannon listened to a certain public radio station 10 hours per week and contributed $35 to the station. Of the following, which is closest to Shannon's contribution per minute of listening time last year?

A. $0.001
B. $0.010
C. $0.025
D. $0.058
E. $0.067

PS08090.02

A. $0.001
B. $0.010
C. $0.025
D. $0.058
E. $0.067

PS08090.02

BrentGMATPrepNow · Accepted Answer

1 hour = 60 minute
So,  10 hours = 600 minutes , which means Shannon listened to 600 minutes PER WEEK
Since there are 52 weeks in a year, the total number of MINUTES = (52)(600) ≈ (50)(600) ≈  30,000

So, Shannon contributed  $35  for  30,000  MINUTES of listening time.
Divide both quantities by 30,000 to get: Shannon contributed  $35/30,000  for  1  MINUTE of listening time.
In other words, Shannon's contribution is  $35/30,000  per minute

At this point, we did not use long division to evaluate  $35/30,000 
Instead, recognize that 30/30,000 = 1/1,000 = 0.001

This tells us that  $35/30,000  is a little bit bigger than 0.001

The closest answer is A

Cheers,
Brent

abalodi · Answer

question asks for contribution per minute "last year." Would need to get the total minutes based on 52 weeks in the year. Upon solving via this logic, i got answer choice A.

Could someone please confirm the correct answer?

itspCv2 · Answer

Straight to point: 365 days= 52 weeks per year 52*10*60 minutes in total per year >>>35/52*10*60=approximately $.001 OA:A HOPE this helps. THANKS

PhantomAY · Answer

So the equation we have 35/(10*60*52) ~ 36/(10*60*52) = 0.06/52 ~ 0.001

Rebaz · Answer

Is it wise to convert the $35 to cents 35 * 100 = 3500 cents and then divide it by 10*52*60 ($10*52 weeks *60 min/hour)?

IanStewart · Answer

The answer we're looking for is expressed in dollars, so I wouldn't suggest changing the unit of dollars into cents. Doing that does temporarily make the numbers a bit easier to look at, but you also need to remember to convert your cents back into dollars at the end, which is an easy step to forget under test conditions. In general, I'd only convert units when the question requires it (as this question does, with the quantity of time, which is expressed in hours in the information in the stem, but in minutes in the question asked).

I don't have much to add to the solutions posted earlier, though I'd always glance at answer choices in a question like this to judge how liberally I can estimate, before doing any calculation. Answers D and E are close in value, but the other answers are far apart. Since the answer to this question needs to be minuscule, I'd assume immediately that D and E are wrong, and round everything off to very simple numbers.

GMATCoachBen · Answer

We can do this quickly if we notice a few things:
  "closest" is a signal to round; additionally, the answer choices have a wide spread. We can round 52 weeks in a year to 50. 
 The question asks for "contribution per MINUTE". We must be careful and convert the time units: "week", "minute", and "year".
10 hours/week * 60 minutes/hour * 50 weeks/year = 30,000 minutes 
 "per" means divide, so "contribution per minute" means $35 / 30,000 minutes

Key habits to prevent a mistake:
  Make sure to always READ carefully and not mix up the units. It's particularly important to double-check what it's asking for. 25% of people get trapped by D, which would be correct if the question said "last WEEK" instead of "last YEAR".  
 Double-check the number of significant figures; the second most common trap here is to choose B. 
 For the division, one way is to quickly and carefully write out the long division as shown below.   
Brent showed another great way above, which is to round 35,000 to 30,000. 30 / 30,000 = 1/1,000 = .001

zoezhuyan · Answer

hi experts, I wonder how can I get the $35 refers to a week or the whole last year ?

GMATCoachBen · Answer

zoezhuyan  It's implied that the $35 is for the whole year. The word "AND" grammatically connects two completely separate actions. The "per week" only applies to the first action below:

Last year Shannon:

1) listened to a certain public radio station 10 hours per week AND

2) contributed $35 to the station.

GMATCoachBen · Answer

Video solution here (3:23):

https://www.youtube.com/watch?v=FP_9-F6kwTw

kanikaa9 · Answer

Since this was calculation heavy, I glanced at the options and they were far apart so I was sure I can use approximation here.

First I calculated total minutes last year = 10 hrs (per week) x 60 (1 hr = 60 min) x 52 (total weeks in a year) -  now don't start calculating and make this 52 > 50

Now I have $35 contribution, i need to find contribution per minute. = 35/600 x 50
 To make calculation even easier, I can write 50 as 100/2  
So this becomes 35x2/600x100

We can easily calculate this and see the  answer is 0.001 i.e. A

arunbhati · Answer

Hi Sir,

How we know that USD 35 is for complete year. I interpreted as USD 35 is for 10 hour/ week.

how to avoid this mistake because from problem, i am not able to understand

Bunuel · Answer

The stem says: “ Last year  Shannon listened ... and contributed $35 to the station.” Both facts are explicitly tied to last year. So $35 is the total contribution for the entire year, not a weekly amount. The “10 hours per week” only describes the listening rate, which you then multiply by 52 to get total listening time for the year.

How to avoid the mistake: when a sentence starts with a time frame like “Last year,” treat everything that follows in that sentence as happening over that same time frame unless the problem clearly says otherwise.